sed: 1: " '/regex/ ...": invalid command code '

Question

I'm trying to write a program to automatically assemble and run sed commands. I'm using the following code snippet to generate commands:

switch command {
case "=", "d":
    return fmt.Sprintf("'/%s/ %s'", regex, command)
case "c", "a", "i":
    return fmt.Sprintf("'/%s/ %s\\\n%s'", regex, command, phrase)
case "s", "y":
    return fmt.Sprintf("'%s/%s/%s/'", command, regex, phrase)
default:
    return ""
}

Then I use the following code snippet to run the full command:

fmt.Println("Running command: sed", args)
program := exec.Command(programName, args...)
output, err := program.CombinedOutput()
fmt.Printf("%s", output)
if err != nil {
    fmt.Println(err)
}

Which results in the following output (Generating 100s of commands, this is just 1):

Running command: sed [-e '/([0a-z][a-z0-9]*,)+/ c\
abc said he""llo!!!\n    1  ' -e '/(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)(l)/ a\
0,0,0,156, aac' -e '/(s?)a.b,a\nb/ d' -f number_lines.txt -f eliminate_punctuation.txt -f delete_leading_trailing_whitespace.txt -f delete_last_ten_lines.txt -f eliminate_blanks.txt -f number_non_blank_lines.txt -f reverse_lines.txt -f strip.txt input1.txt input2.txt input3.txt]

sed: 1: " '/([0a-z][a-z0-9]*,)+/ ...": invalid command code '
exit status 1

That's weird, but what's weirder is if I run the generated command by hand (Without the square brackets of course), it works just fine! What's going on here?

abhink · Answer 1 · 2016-10-19T06:21:18.930

Shell strips the quote characters, exec.Command does not. So it could be that sed is being passed the ''s with the commands. Try forming the command without the single quotes:

switch command {
// remove single quotes from strings
case "=", "d":
    return fmt.Sprintf("/%s/ %s", regex, command)
case "c", "a", "i":
    return fmt.Sprintf("/%s/ %s\\\n%s", regex, command, phrase)
case "s", "y":
    return fmt.Sprintf("%s/%s/%s/", command, regex, phrase)
default:
    return ""
}

sed: 1: " '/regex/ ...": invalid command code '

1 Answers1